Sheet associating apparatus



Sept. 13, 1955 BAKER ET AL 2,717,710

SHEET ASSOCIATING APPARATUS 3 Sheets-Sheet l Filed Aug. 17 1950 ATTORNEY.

Sept. 13, 1955 BAKER ET AL 2,717,710

SHEET ASSOCIATING APPARATUS Filed Aug. 17, 1950 5 Sheets-Sheet 2 INVENTORS. flaw/m1 [5W 00010 a. dam/L ATTORNEY.

p 3, 1955 L. BAKER ET AL 2,717,710

SHEET ASSOCIATING APPARATUS q 5% a7 51 Py m- 19 452, E. 6am

ATTORNEY.

United States Patent Rounsefell, Pearl River, N. Y., assignors, by mesne assignments, to Dexter Folder Company, Pearl River, N. Y., a corporation of New York Application August 17, 1950, Serial No. 179,912

18 Claims. (Cl. 21625) This invention relates to sheet associating apparatus and more particularly to apparatus for applying and adhesively securing sheets to articles.

The invention is particularly, but not exclusively, concerned with the application of sheets having a coating of a pressure sensitive adhesive material on one side thereof to apertured cards for the mounting of micro-films and other inserts in said cards. The invention will be particularly described in connection with apparatus suited to such use, but it is to be understood however that this particular description is for the purpose of illustration only and does not constitute a limitation upon the natural scope of the invention.

One of the objects of the present invention is to provide novel, simple and effective apparatus for applying and adhesively securing sheets to cards, as well as to other articles having a planar surface.

Another object of the invention is to provide novel apparatus which will effectively apply sheets having a coating of a pressure sensitive adhesive material on one side thereof to cards and other articles having a flat surface.

Another object is to provide novel apparatus of the character designated which will effectively and accurately apply small sheets of a relatively thin transparent material to cards and over an aperture in said cards, said sheets being coated on one side thereof with a layer of pressure sensitive adhesive material.

Another object is to provide novel apparatus for cutting sheets successively from a narrow web or strip of thin transparent material coated on one side thereof with a layer of pressure sensitive adhesive material, and for applying said sheets to cards or the like.

A further object is to provide novel apparatus of the above character wherein the sheets during severance thereof from the web or strip and until the same are applied to the cards or the like are maintained under positive control.

Still another object is to provide apparatus of the above character embodying cutting means of novel construction for severing the successive sheets from the pressure sensitive adhesive web or strip, and which also operate to positively grip, transfer and apply the severed sheets in fiat condition to the cards or other articles.

Another object is to provide apparatus of the character designated having novel cutting means so arranged that after severance of each sheet from the pressure sensitive adhesive web or strip, the latter is stripped from said cutting means, whereby upon subsequent feeding of said webor strip, movement of the latter into position for cutting of the next sheet therefrom is positively assured.

Another object is to provide apparatus of the above character embodying novel means for drawing the pressure sensitive adhesive web or strip from a supply roll thereof and feeding said Web or strip into cutting position.

A still further object is to provide a novel method "ice of rendering a projected portion of a narrow webor strip of relatively thin material self-supporting, whereby proper feeding and positioning of said web or strip portion for action thereon, such as for cutting sheets therefrom, is greatly facilitated.

The above and further objects and novel features of the present invention will more fully appear from the following detail description when the same is read in connection with the accompanying drawings. It is to be expressly understood, however, that the drawings are for the purpose of illustration only, and are not intended as a definition of the limits of the invention.

In the drawings, wherein like reference characters refer to like parts throughout the several views,

Fig. l is a side elevational view, partly in section, of a sheet associating apparatus constructed in accordance with the present invention;

Fig. 2 is a front elevational view of the major upper portion of said apparatus;

Fig. 3 is a detail top plan View, partly in section, showing the operating means for the adhesive sheet severing and applying means;

Fig. 4 is a vertical longitudinal sectional view of said apparatus taken substantially on the line 44 of Fig. 2, drawn to an enlarged scale and with certain of the parts having portions thereof broken away for purposes of clearer illustration; I

Fig. 5 is a fragmentary vertical transverse sectional view taken substantially on the line 55 of Fig. 4;

Fig. 6 is a detail top plan view, partly in section, showing the pneumatic feeding means for the adhesive Web or tape;

Fig. 7 is a fragmentary side elevational view, showing the parts of the adhesive sheet severing and applying means in the positions they occupy when a severed sheet is applied to a card;

Fig; 8 is a detail top plan view, partly in section, of the adhesive sheet severing and applying means;

Fig. 9 is a perspective view, showing a method of and means for rendering a projected portion of the adhesive web or strip self-supporting;

Fig. 10 is an enlarged vertical transverse sectional View of a rotary valve shown in Fig. 2;

Fig. 11 is a face view of one form of card adapted to be utilized insaid apparatus; and

Fig. 12 is a face view of said card with an adhesive sheet applied thereto.

In the drawings, there is shown, by way of example, one form of sheet associating apparatus constructed in accordance with the present invention which is particularly adapted for cutting sheets successively from a narrow supply web or tape of relatively thin transparent material, such as cellulose acetate, coated on one side thereof with a layer of pressure sensitive adhesive material, and for applying said sheets to apertured cards for the purpose of mounting micro-films and other inserts of a similar character in said cards. In a commercial embodiment of the invention, the adhesive coated sheets are applied to cards of the record type commonly employed in known and existing statistical card tabulating and sorting systems and machines, whereby the films or other inserts mounted in said cards may be conveniently classified and sorted mechanically as to subject matter in a manner understood in this art, as well as viewed, examined, indexed, and filed. One card of this statistical type is shown, for purposes of illustration only, in Figs. 11 and 12 and indicated at 15, said card being oblong in shape and made of cardboard or heavy relatively stifi paper material. It will be understood that the present invention is not limited to the application of the adhesive coated sheets to the statistical or tabulating machine type of card since said sheets may be applied to other forms of apertured record or catalogue cards, as well as to ordinary cards for the same purpose. Additionally, the present invention comprehends the use thereof for adhesiveiy applying pressure sensitive adhesive sheets, as well as other adhesive and non-adhesive sheets of various types and materials, to envelopes, sheets, cartons, boxes, and other articles for various purposes.

As shown in Fig. 11, card is provided at a selected position with a generally rectangular aperture 16 of an appropriate size to receive the film or other insert therein. As shown in Fig. 12, card 15 has applied thereto on one face thereof and over the aperture 16 a sheet 17 of thin clear transparent material, such as cellulose acetate, having a coating of pressure sensitive adhesive material thereon to hold the film or other insert firmly in place when inserted in said aperture.

Referring now to Figs. 1 to 10, inclusive, of the drawings, the various movable parts, as well as certain stationary parts, of the novel apparatus comprehended by the present invention for applying the adhesive coated sheets 17 to the cards 15 or other articles, are all mounted on a suitable frame comprising a bed plate 18 bolted or otherwise suitably secured at opposite sides thereof to two transversely spaced standards 19 and 20 which rest on the machine foundation (Figs. 1 and 2). The various movable parts of the apparatus may be driven by any suitable means which may comprise a V-belt 21 (Fig. 1) driven from any suitable source of power (not shown) and passing around a pulley 22 which is fixed on the outwardly projecting end of a short shaft 23 journalled in a suitable bearing in the standard 2%. Fixed on the inwardly projecting end of shaft 23 is a spur pinion 24 which meshes with a spur gear 25 that is fixed on a transversely extending shaft 26 journalled at opposite ends thereof in suitable bearings in the standards 19 and 20. This shaft 26 makes one complete revolution for each cycle of operation of the apparatus and is utilized to operate various parts of said apparatus to be hereinafter described.

Bolted or otherwise suitably secured to the upper surface of the bed plate 18 is a vertically projecting bracket 27 (Fig. 2) having bolted or otherwise suitably secured to the upper end thereof a bracket 28. Fixed in the bracket 28 and projecting laterally therefrom is a short shaft 29 which is adapted to rotatably support a supply roll 30 of tape 31 of thin transparent material, such as cellulose acetate, having on one side thereof a coating of pressure sensitive adhesive material which is normally protected by a readily removable covering strip 32, such as glassine paper or the like (Figs. ,1 and 4). The tape 31 is of a width suflicient to cover the aperture 16 in the card 15 and to extend over and adhere to said card at opposite marginal side edges of said aperture. The supply roll 31) is retained in proper position on shaft 29 by annular plates 33 disposed at opposite sides of said roll and adjustably secured to said shaft by thumb screws 34 or the like. Plates 33 are provided with elongated openings 35 to visibly determine the quantity of tape 31 on roll 33 during the operation of the apparatus.

As shown in Figs. 1 and 4, the tape 31 with the protective covering strip 32 adhering thereto is drawn from the supply roll 30 and threaded rearwardly between a rubber covered pressure roller 36 and a suction feed cylinder 37 such that said tape is in contact with said pressure roller. After threading of the combined tape 31 and covering strip 32 between the pressure roller 36 and suction cylinder 37, said covering strip is peeled from the leading end of said tape and directed upwardly and forwardly around said pressure roller and then threaded between the latter roller and an auxiliary rubber covered pressure roller 38. From the pressure rollers 36, 38 the covering strip 32 may be directed upwardly and rearwardly around the roller 38 to a suitable disposal point. After the covering strip 32 is peeled from the tape 31 as described, said tape is directed downwardly and forwardly around the rear half of the suction cylinder 37, whereby the non-adhesive side of the tape is in contact with the cylinder and the coating of pressure sensitive adhesive material is disposed on the outside of said tape. As hereinafter described, the suction cylinder 37 operates to positively grip the tape 31 and feed the same forwardly into position for cutting of individual sheets 17 therefrom by cutting means to be hereinafter described, and as said tape is so fed, the coacting pressure rollers 36, 38 operate to progressively peel the protective covering strip 32 from the tape.

The pressure roller 36 is fixed on a short shaft 39 which is journalled at opposite ends thereof in suitable bearings provided in spaced parallel arms it? which extend rearwardly and downwardly from said roller and are connected together at their upper front ends by a transverse web 41 formed integrally therewith, and at their lower rear ends by a transverse hub 42 also formed integrally therewith (Figs. 1, 2 and 4). The arms 4-15 are secured to a short shaft 43 which extends through the hub 42 and is journalled for pivotal movement at opposite ends thereof in suitable bearings provided in spaced parallel side walls 414 and 45. These side walls 44, 45 form an integral part of a main supporting bracket 46 which is bolted or otherwise suitably secured adjacent the bracket 27 to the upper surface of the bed plate 18. The pressure roller 38 is secured to a short shaft 47 the opposite ends of which project into suitable elongated openings 43 formed in the arms 40. These openings 48 provide for free floating vertical movement of roller 38, and permit raising of said roller to facilitate threading of the covering strip 32 between the same and the roller 36. The combined tape 31 and covering strip 32 is main tained in proper lateral position and is guided from the supply roll 36 to and between the suction feed cylinder 37 and the coacting pressure roller 36 by two forwardly projecting Wings 4) which are disposed on opposite sides of the path of movement of said tape and strip and are adjustably secured to the connecting web of the arms 40.

As best shown in Figs. 4, 5 and 6, the suction feed cylinder 37 is disposed between the side walls d5 of bracket 46 and is provided centrally thereof with a plurality of spaced rows of small openings 50 which are equally spaced about the entire periphery of said cylinder and communicate with the interior thereof. The openings 56 are flared or countersunk at their outer ends, as indicated at 51 (Fig. 6), whereby the tape grip ping vacuum area of the cylinder 37 is increased. Cylinder 37 is closed at opposite ends thereof by annular cover plates 52 and 53 secured thereto at said or by suitable means, such as flathead machine screws Plates 53 provide suitable bearings for rotatably supporting the cylinder 37 on a shaft 55 which extends transversely of the bracket 46 and is supported at opposite ends thereof in the side walls 34, of said bracket. Shaft :35 is provided in one end thereof with an axial bore 56 of a predetermined depth, is fixed at the opposite end thereof against rotation relative to bracket 46 by suitable set screw means 57 provided in the side wall 45 of bracket and engaging a reduced portion 53 of said shaft. The open end of shaft 575 projects beyond the side wail 44 of bracket 46, and said shaft is formed at sai end with an enlarged head 59 for a purpose to appe hereafter. Shaft 55 is further provided with a pluraiity of axially spaced openings 6%, three being shown, which communicate with the bore 5'6 in said shaft and open outwardly through one side only of the shaft, said open ings being so located that they are in alignment with the rows of openings 50 in cylinder 37.

Threaded into the head 59 or" shaft 55 and communicating with the bore 56 in said shaft is a tubular fitting 61 having connected therewith one end of a flexible conduit 62 (Figs. 1 and 2). The opposite end of conduit 62 is connected, as at 63, to a conventional rotary pump 64 suitably constructedto supply air under pressurefrom one side thereof and to create vacuum in another side thereof, said connection. 63 being made at the vacuum side of said pump. The pump 64 is suitably mounted within the frame work of the apparatus and is continuously driven by an electric motor (not shown) suitably connected with the rotor shaft 65 of said pump. Vacuum is thus continuously created in the feed cylinder 37 and openings 58 by pump 64 through fittings 61, 63, conduit 62, shaft 55 and openings 60 to cause the tape 31 to adhere to said cylinder for positive feeding movement thereby upon rotation thereof.

Disposed within and snugly fitting the feed cylinder 37 is a shoe 66 (Figs. 4 and 6) by means of whichvacuum created in said cylinder is, in accordance with one aspect of the present invention, confined'to the entire rear half thereof and concentrated at the openings 50, whereby a substantial portion of the tape 31 will be firmly and .continuously gripped by the cylinder at a plurality of. spaced points beginning substantially at the pressure roller 36 and ending substantially at a point diametrically opposite said roller. In this manner, slipping of the tape 31 relative to the cylinder 37 is completely eliminated, and positive feeding of a predetermined amount of said tape by saidcylinder during each cycle of operation of the apparatus is always assured. For this purpose, the shoe 66 is vertically arranged within the cylinder 37 and is provided with a transverse dividing wall 67 disposed forwardly of the shaft 55 and having its upper and lower ends located substantially on the vertical center line of the cylinder, and two rearwardly projecting spaced parallel side walls 68 and 69 which are curved to correspond with the curvature of the inner face of the cylinder and are disposed at opposite sides of the openings 50 and 60 in said cylinder and shaft 55, respectively, to enclose the same. The shoe 66 is engaged over the shaft 55 and is fixed against rotation with the cylinder 37 by means of a gib 70 which is riveted or otherwise suitably secured to the wall 69 of said shoe and adapted to engage a flat '73 formed in the periphery of said shaft adjacent the reduced portion 58 thereof, when the shaft is rotatably positioned in bracket 46 by means of the head 59 that the openings 60 in said shaft are directed toward the rear of the cylinder, as shown in Figs. 4 and 6.

It will thus be apparent that when the tape 31 is passed downwardly and forwardly around the rear half of the feed cylinder 37 in the initial make-ready of the apparatus, all of the openings 50 registering with the vacuum chamber defined by the walls 68, 69 of shoe 66 will be sealed by said tape and, hence, a strong vacuum will exist in said cylinder and in said openings to cause the tape to firmly adhere to the peripheral surface of the cylinder. It will also be apparent that when the cylinder 37 is rotated in a counter-clockwise direction, as viewed in Fig. 4, during the normal operation of the apparatus to positively feed the tape 31 through pneumatic gripping action exerted thereon, the openings 50 in operative connection with the vacuum chamber will pass forwardly in succession beyond the lower end of the dividing wall 67 of shoe 66 out of registry with said chamber and into communication with the atmosphere. Accordingly, as the openings 50 reach the lowermost point of the cylinder 37 vacuum is broken in said openings successively, whereupon the tape 31 is released from the cylinder at said point for further movement beyond said cylinder. Likewise, upon rotation of the cylinder 37 in the described direction, the openings 50 out of registry with the vacuum chamber will pass rear,- wardly in succession beyond the upper, end of the dividing wall 67 and into operative connection with. said chamber, whereupon succeeding portions of the tape 31 drawn from the supply roll 30 will be pneumatically gripped and maintained in intimate contact with the periphery of the cylinder. The dividing wall 67 of shoes 66 thus also serves to control the pneumatic-grip- 6 pingactionof the cylinder 37 so that the tape 31 will be firmly. gripped throughout a certain part of the path of travel of said cylinder and will be released upon arriving at a predetermined point.

Before proceeding with the description of the pneumatic tape feeding means, it might be mentioned that the pressure roller 36 rests on the feed cylinder 37 by gravity under its own weight and the weight of the overhanging arms 40 and other elements carried by said arms, and that said roller is rotated by said cylinder through frictional contact of the same with the combined tape 31 and covering strip 32. The pressure roller 38 freely rests by gravity under its own weight on the roller 36 and is driven by the latter roller through. frictional contact of the same with the covering strip 32. If desired, suitable spring means connected with the arms 40 and the roller 38 may be provided to obtain increased traction of said roller and the roller 36 on the covering strip 32.

The feed cylinder 37 is intermittently rotated a portion of a revolution to feed a predetermined length of the tape 31 past the same into cutting position during each cycle of operation of. the apparatus. This intermittent operation of the cylinder 37 may be effected in any suitable manner and by any suitable means, and as herein shown is effected by mechanism constructed, mounted and operated as follows. Secured to the driven shaft 26 is a pulley 74 (Fig. 1) around which passes a V-belt 75* which also passes around and drives a similar pulley 76. This pulley 76 is fixed on the outer end of a short shaft 77 which is journalled in a suitable bearing at thecupper end of the bracket 27. Pulleys 74, 76 are of the same diameter and, hence, shaft 77, like shaft 26, makes one complete revolution for each cycle of operation of the apparatus.

Pinned or otherwise suitably secured to the inner end of shaft 77 for rotation thereby is a spur gear 78 (Figs. 1, 2 and 4). Disposed in face to face relation with gear 78 is an eccentric disc 79. which is releasably clamped to said gear for rotation therewith and for adjustment relative thereto by means of a shoulder bolt 80 and a machine screw 81. Bolt 80 projects through suitable clearance openings in the disc 79 and gear 78 and is threaded into the inner end of shaft 77, and screw 81 projects through an arcuate slot 82 in said disc and is threaded into said gear. Journalled on the disc 79 is the upper end of a connecting rod 83 the lower end of which is pivotally connected to the outwardly projecting end of a stud 84 which is journalled in a suitable bearing provided in a pawl carrier 85. Disc 79 is provided with an external annular flange 86 to retain the connecting rod 83 thereon.

The pawl carrier is disposed exteriorly of the side wall 45 ofv bracket 46 and is journalled for oscillating movement by the eccentric disc 79 and connecting rod 83 on a hub 87 of a ratchet 88 (Figs. 4 and 6). Pivotally mounted on the inwardly projecting end of stud 84 in pawl carrier 85 is apawl 89 which is yieldingly held in engagement with the teeth of ratchet 88 by suitable resilient means, such as a leaf spring 90 which is suitably secured at one end thereof to the top of said carrier and has a laterally and inwardly directed portion engaged with the top of said pawl.

The ratchet 88 is keyed or otherwise suitably secured to the outwardly projecting endof a spindle 91 (Figs. 2,4 and 6) which is journalled in a suitable bearing provided in the side wall 45 of bracket 46. Keyed or otherwise suitably secured to the inwardly projecting end of shaft 91. for rotation with said shaft is a spur gear 92- which meshes with and drives a spur pinion 93 which is loosely engaged over the reduced end 58 of shaft 55 and is pinned or otherwise suitably secured'to the cover plate 53 of the feed cylinder 37.

It will thus appear that through oscillation of the pawl carrier 85 by the describedoperating connections there- 7 for with shaft 77 and engagement of the oscillating pawl 89 with the ratchet 88, the feed cylinder 37 will be rotated by the gears 92, 93 a portion of a revolution in a counter-clockwise direction, as viewed in Fig. 4, to feed the tape 31 adhering thereto in a forward direction. The stroke of the pawl carrier 85 and the gears 92, 93 are so chosen that upon each operation of the feed cylinder 37 the tape 31 will be fed an amount suflicient to cover the aperture 16 in the card 15 and to extend over and adhere to said card at the upper and lower marginal edges of said aperture. in order to enable adjustment of the tape feed by cylinder 37, a pawl mask 94 (Fig. 4) is secured to the top of the side wall 45 of bracket 46 for adjustment along the path of oscillating movement of the pawl 89. The mask 94, when adjusted to operative position, acts to hold the pawl 89 out of engagement with the ratchet 88 for a portion of the power stroke of the pawl carrier 85, thus controlling the extent of rotation of the feed cylinder 37 by the ratchet 88 and gears 92, 93 to a desired degree.

In order to eliminate overtravel or coasting of the feed cylinder 37 upon each operation thereof by the described means for this purpose, and variations in the tape feed resulting therefrom, a frictional drag is continuously applied to said cylinder, said frictional drag also operating to hold the cylinder in each actuated position and against return movement as the pawl carrier 85 and pawl 89 are returned for the next cycle of operation. This frictional drag may be effected by any suitable brake means, and as herein shown is effected by a spring-pressed button 95 (Figs. 4, and 6) of a suitable relatively soft material, such as brass, leather, rawhide or the like, which is slidably carried in an externally threaded sleeve 96 and is yieldingly engaged with the outer face of the cover plate 53 of the feed cylinder 37. Sleeve 96 is adjustably threaded in a bracket 97 which extends across and is bolted or otherwise suitably secured to the front ends of the side walls 44, 45 of bracket 46. The spring for button 95 is indicated at 98 and is disposed within the sleeve 96, said spring being of the coil compression type and having one end thereof engaging against the outer wall of said sleeve and the opposite end engaging against the inner end of said button. Rotation of the sleeve 96 in opposite directions will increase and decrease the pressure of the button 95 on the cylinder 37 to obtain the desired degree of frictional drag of said button on said cylinder. The axial thrust imposed upon the feed cylinder 37 by the button 95 is absorbed by a suitable antifriction thrust bearing 99 which is loosely engaged over the shaft 55 and is disposed between the cover plate 52 of said cylinder and a spacer shim or washer 100 also loosely engaged over said shaft. A similar spacer shim or washer 161 is loosely engaged over the reduced end 58 of shaft 55 and is disposed between the pinion 93 and the adjacent side wall 45 of bracket 46. said shim and the shim 1150 providing for location of the feed cylinder 37 in proper axial position on shaft 55.

As the tape 3 during each cycle of operation of the apparatus is fed forwardly by the suction cylinder 37 with the coating of pressure sensitive adhesive material now on the underside thereof, the leading portion of said tape as it is progressively released by said cylinder is, in accordance with another aspect of the present invention, progressively bowed transversely so as to stiffen the same in a longitudinal direction. In this manner, the released leading portion of the tape 31 is made self-supporting and prevented from bending or curving downwardly, and is caused to freely project and move straight forward beyond the cylinder 37 and into cutting position along a horizontal path substantially tangent to the lowermost point of said cylinder. Sticking and jamming of the tape 31 in the machine is thus avoided, and accurate feeding of said tape, accurate cutting of the individual sheets 17 therefrom, and accurate flatwise application of said sheets to the cards are thus always assured.

This bowing and stiifening of the released leading portion of the tape 31 is novelly effected by air jet means which comprise a blow pipe 102 disposed exteriorly of the bracket 46 adjacent the side wall 44 thereof. Pipe 182 has a forwardly extending downwardly inclined portion 1&3 which is offset inwardly and disposed beneath and centrally with respect to the feed cylinder 37 and the openings 50 in said cylinder (Figs. 1, 2, 4 and 5). A plug 104 is suitably secured in each end of the pipe 102 to tightly seal the latter against any escape of air under pressure. The portion 103 of pipe 102 is provided at the top and inwardly from the free end thereof with twin air jet openings 105 (Figs. 4, 5 and 9) and a plurality of single air jet openings 1% axially spaced beyond said twin openings toward said free end of said pipe portion. The air jet openings are so located that the twin openings 105 are closest to the suction feed cylinder 37, whereby the double air jets issuing from said openings will strike the tape 31 with maximum force and susbtantially at the point of release of said tape by said cylinder, and that the single openings 106 are gradually spaced farther away from said cylinder in a longitudinal direction and from the tape 31 in a vertical direction, whereby the single jets of air issuing from the latter openings will strike said tape along the same with gradually diminishing force.

The rear end of the blow pipe 1192 projects through aligned openings formed in a stud 197 and in a sleeve 108 telescoped over said stud (Figs. 1 and 3). Stud 197 projects through a suitable opening in a split-arm 109 slidably engaged over a vertically extending post 111) which is suitably secured at its lower end in the bracket 46. A nut 111 is threaded onto the inwardly projecting end of stud 107, and it will thus be apparent that upon tightening said nut, said stud will be drawn inwardly relative to sleeve 108, whereupon blow pipe 1112 will be immovably clamped against said sleeve by the stud, and arm 109 will be immovably clamped to post 116 by said stud through the sleeve.

Air under pressure is continuously supplied to the blow pipe 102 by the pump 64, and for this purpose said pipe is provided with a fitting 112 (Figs. 1 and 2) which is suitably bored and communicates with the interior of the pipe through a suitable opening in the latter. Connected with the fitting 112 is one end of a flexible conduit 113 the opposite end of which is connected with a compressed air tank 114 which is suitably supported within the framework of the apparatus. Tank 114 has connected therewith one end of a flexible conduit 115 the opposite end of which is connected with the exhaust or air pressure side of the pump 64. Air under pressure will, through the described connection between pump 64 and tank 114, thus be continuously maintained in said tank and in the conduit 113, fitting 112 and blow pipe 102.

Cooperating with the air jet means to effect the transverse bowing and resulting longitudinal stilfening of the released leading portion of the tape 31 is a horizontal guide plate 116 (Figs. 4, 5 and 9). This guide plate 116 is disposed in close proximity to the suction feed cylinder 37 and above the path of forward movement of the released leading portion of the tape, and has opposite side portions or halves slightly bent upwardly so that said guide plate is in effect slightly V-shaped in transverse cross-section. Plate 116 is suitably secured, as by flathead machine screws 117, adjacent the forward end thereof to correspondingly shaped surfaces on the underside of the bracket 97. Plate 116 is so located that the apex thereof is substantially tangent with the bottom of the feed cylinder 37 and is centrally disposed with respect to the tape 31 and the openings 50 in said cylinder. The length of the guide plate 116 is so proportioned with respect to the air jets issuing from the openings 105, 1116 in the blow pipe portion 103 that the air jet issuing from the opening 106 nearest the free end of said blow pipe portion will fully strike said plate and not project beyond the forward end thereof.

It willthus appear that as the tapev31 is advanced and progressively released by the feed cylinder 37, the released portion of said tape will immediately be blown into intimate contact with the guide plate 116 by the twin air jets 105 and thereafter held in such contact with said plate by the single air jets 186, As a consequence of this, the released portion of the tape 31 is caused to move straight forward beyond the feed cylinder 37, and is transversely bowed to stiffen the same longitudinally so that the leading end portion thereof is caused to unsupportingly project straight forward beyond the forward end of the guide plate 116 without curving or bending downwardly. It will be noted that the air jets 105, 106 further provide a pneumatic support for the tape 31 and, hence, said tape at the adhesive coated side thereof is totally free from contacting any physical element or elements which would interfere with or prevent the free forward movement thereof. If desired, a slightly concave guide plate may be used effectively in lieu of the slightly V-shaped guide plate 116.

As the bowed and stiffened portion of the tape 31 leaves the forward end of the guide plate 116, it projects straight forward under a normally raised, vertically movable cutoff knife 118 in the form of a horizontally disposed plate whose cutting edge is at the rear edge thereof (Fig. 4). Upon each operation of the feed cylinder 37, the tape 31 is advanced beyond the cutting edge of the knife 118 a distance corresponding to one dimension of the sheet 17 appropriate to one card 15. The knife 118 coacts with a horizontally disposed normally stationary cut-off knife 119 which is arranged below and adjacent the forward end of the guide plate 116, and is spaced from said plate and the tape 31 to avoid contact of said tape with said knife during the forward movement thereof into cutting position, the cutting edge of said knife being formed at the front edge thereof.

The cut-off knife 118 is adjustably secured by suitable means, such as flathead machine screws 120 and nuts 121 (Figs. 7 and 8), to an external rectangular flange 122 which is secured to or formed integrally with a vertically extending hollow plunger 123 at the lower end thereof (Fig. 4). The screws 120 pass through suitable circular openings in the knife 118 and through suitable slotted openings in the flange 122, and the heads of said screws are embedded in and flush with the lower surface of said knife so that said surface is smooth and flat for a purpose to appear hereafter. The flange 122 is provided in the lower surface thereof with a rectangular chamber 124 which is in communication with the hollow plunger 123 and with a series of small openings 125 which are arranged in a rectangular pattern in the knife 118 and open outwardly through the lower surface thereof.

The plunger 123 is slidably fitted for vertical reciprocation in a boss 126 which is formed integrally with the bracket 97 (Figs. 1, 2 and 4). Loosely engaged over the reduced and partially threaded upper end of the plunger 123 is a transversely extending yoke 127 which is held against relative upward displacement by nuts 128 threaded on said plunger end. Pivotally connected to opposite ends of the yoke 127 are the upper ends of vertical links 129 and 130 the lower ends of which are pivotally connected to the free forward ends of two transversely spaced driving arms 131 and 132, respectively (Figs. 1 to 4). These arms 131, 132 extend rearwardly outside of the arms 40 and then downwardly inside of the side walls 44, 45 of bracket 46 and are fixed at their lower ends to a short transversely extending shaft 133 which is journalled in suitable bearings in said side walls. The arms 131, 132 are connected together in spaced parallel relation by two tie-bars or pins 134 which are suitably secured thereto adjacent the front and rear ends thereof, and said arms are provided adjacent the pivotal axis 133. with inwardly projecting vertically extending lugs 135 and 136, respectively.

Loosely mounted on the shaft 133 for relative pivotal movement and bridging the space between the arms 131, 132 is a bell-crank lever consisting of a forwardly ex: tending arm 137 (Figs. 1, 3 and 4) and a plate-like upwardly projecting arm 138 which is disposed rearwardly of and overlaps the lugs 135, 136 on arms 131, 132, respectively. Extending loosely through suitable axially aligned openings in the lug and the arm 138 is a rearwardly projecting rod 139 which is externally threaded at the rear end thereof and is provided at the front end thereof with an enlarged head 140 engaging against the front surface of said lug. The head 140 on rod 139 is formed with a suitable hook 141 which projects over the side of the lug 135 to hold said rod against rotation relative to said lug. Surrounding the rod 139 is a compression coil spring 142 having one end engaging against a retaining washer 143 which, in turn, engages against the rear face of the arm 138, andthe opposite end engaging against a similar retaining washer 144 which, in turn, engages against an adjusting nut 145 threaded on said rod. Nut 145 is held in adjusted position by a suitable lock nut 146 also threaded on the rod 139. The arm 131 is further provided with a second relatively short arm 147 (Fig. l) which extends rearwardly of the pivotal axis 133 and has adjustably threaded therein a hardened steel stop-screw 148 which is adapted to engage a hardened steel plug or button 149 fixed in the bracket 46. Stopscrew 148 is held in adjusted position by a suitable lock nut 150 threaded thereon and engaging against the arm 147.

Adjustably carried by the plate-like arm 138 of the bellcrank lever at the side thereof opposite the rod 139 is a contact member 151 (Figs. 3 and 4) in the form of a hardened steel screw which is threaded into said arm and is adapted to engage a hardened steel plug or button 152 fixed in the lug 136 of arm 132. Contact member 151 is held in adjusted position by a suitable lock nut 153 threaded thereon and engaging against the arm 138. Pivotally connected to the free end of the bell-crank arm 137 is the upper end of a connecting rod 154 (Fig. l) the lower end of which surrounds and is journalled on an eccentric 155 which is secured to the main operating shaft 26.

It will thus appear that upon rotation of shaft 26 and eccentric 155 in the direction of the arrow indicated in Fig. 1, the bell-crank lever 137, 138 will be positively rocked in a clock-wise direction from the position shown in said figure by said eccentric through the connecting rod 154. Under these conditions, the arms 131 and 132 will be rocked in the same direction through engagement of the contact member 151 with the plug 152 and, hence, the plunger 123 will be moved downwardly through the described connections therefor with said arms. Accordingly, the knife 118 will be moved downwardly by plunger 123 past the cutting edge of the knife 119 and beyond the latter knife a predetermined extent such that it engages the upper surface of a card 15 under pressure, as shown in Fig. 7, whereupon a sheet 17 is first severed from the tape 31 by the knife 118 and thereafter applied by said knife under pressure onto said card surface, said card prior to severance of the sheet 17 from the tape 31 being properly positioned in the machine and supported-on an anvil-block 156 which is disposed directly beneath the plunger 123 and is bolted or otherwise suitably secured to the bracket 46. The extent of downward movement of the knife 118 and, hence, the amount of pressure applied by said knife on the card 15 may be regulated by adjusting the contact member 151 relative to the plug 152 on arm 132.

After the severedsheet 17 is applied to the card 15 as above described, and upon continued rotation of the eccentric 155, the bell-crank lever 137, 138 will be positively rocked in a counter-clockwise direction (Fig. 1) and returned to its original position shown in said figure. Under these conditions, the arms 131, 132 willbe rocked in the same direction through the yielding connection afforded by the spring 142 for a portion only of the return stroke of the bell-crank lever 137, 138 until the stop-screw 143 contacts the plug 149, whereupon the knife 118 will be raised only to the position shown in Figs. 1 and 4 suificiently clear of but relatively close to the path of forward movement of the tape 31, and the spring 142 will yield as said bell'crank lever continues to move the remainder of its return stroke. By virtue of the yielding connection 142 between the bell-crank lever 137, 138 and the driving arm 131, and the separable connection 151 between said lever and the arm 132, the knife 118 is not only positively actuated in both directions, but is quickly raised and positioned in readiness for the next sheet severing operation. The normal raised position of the knife 118 with respect to the tape 31 may be regulated by adjusting the stop screw 143 relative to the arm 147. The operation of the knife 11% is so timed with respect to the feeding movement of the 31 that it occurs during the intermittent non-feeding periods or" said tape.

In order to insure accurate cutting of the sheet 17 from the tape 31 and accurate flatwise application of the severed sheets to the card 15, the knife 11% further novelly operates to pneumatically grip and hold the extended portion of the tape flatwise against the same just prior to and during the cutting of each sheet from the tape, and to thereafter pneumatically hold the severed sheet in flat condition and positively bring it into flatwise contact with a card 15. For this purpose, the upper end of the hollow plunger 123 which carries the knife 113 is further reduced and has connected therewith one end of a flexible conduit 157 (Figs. 2 and 4). The opposite end of conduit 157 is connected with a suitable valve mechanism, indicated generally at 158 (Fig. 2), for controlling the making and breaking of vacuum in the plunger 123, chamber 124 and opening 125 at predetermined intervals such that the extended portion of the tape 31 is gripped by the knife 118 just as the latter contacts said tape portion, and the severed sheet 17 is released by said knife after the latter has completed its downward stroke and has applied said sheet to a card 15.

The valve mechanism 158 may be of any suitable type and construction, and that herein shown is of the rotary type and comprises an open-ended cylindrical casing 159 (Figs. 2 and which is bolted or otherwise suitably secured at one end thereof to the bracket 27. Casing 159 is provided in the periphery thereof with two circumferentially spaced and aligned ports 16% and 161 which communicate with the interior of said casing, the port 16% being connected with the conduit 157 through the medium of a tubular fitting 162 suitably secured in the casing 159. Connected with the port 151 in casing 159 by means of a tubular fitting 163 suitably secured in said casing is one end of a flexible conduit 164 the opposite end of which is connected to the fitting 63 at the vacuum side of pump 64 (Fig. 1). Vacuum is thus continuously applied by pump 64 to the port 161 in casing 159 through the fitting 63, conduit 164 and fitting 163.

Rotatably mounted and journalled within the valve casing 159 and also journalled in a suitable bearing pro vided in the bracket 27 is a rotor 165 (Fig. 10) which is provided in the periphery and between the ends thereof with an arcuate passageway 156 of a predetermined length. Secured to one end of the rotor 165 is a spur gear 167 (Figs. 1, 2 and 4) which meshes with and is continuously driven by the spur gear 78 that is fixed on the single revolution shaft 77. Gear 167 is of the same size as gear 78 and, hence, rotor 65 also makes one complete revolution for each cycle of operation of the apparatus. Rotor 165 is held within the casing 159 by a retaining plate 163 which is bolted or otherwise suitably secured to the opposite end of said casing.

it will thus appear that when the leading end of the passageway 166 moves into registry with the port 161, through rotation of the rotor 165 in a clockwise direction, as viewed in Fig. 10, the plunger 123 will be connected with the vacuum side of the pump 64 through the fitting 63, conduit 164, fitting 163, port 161, passageway 166, port 160, fitting 1'62, and conduit 157. V acuurn will thus be created in the plunger 123 and openings 1215 in knife 113 and maintain therein until a sheet 17 is severed from the tape 31 and firmly applied to a card 15 by said knife, at which time the plunger 123 is disconnected from the pump es and vacuum is broken in said plunger and the knife 118 to release the applied sheet 17, through movement of the opposite or trailing end of the passageway 1&6 out of registry with the port 1611 upon continued rotation of the rotor 165.

In order to insure effective and rapid release of the applied sheet 17 by the knife 113, the plunger 123 is provided with a relief port 169 (Figs. 4 and 7) which comates with the bore in said plunger and opens outly through one side thereof. The port 169 is so located that it is disposed within and closed by the boss 126 of bracket 97 when the plunger 123 and knife 118 a in their normal raised positions, as shown in Fig. 4. en the plunger 123 is moved downwardly and the knife 13 reaches its lowermost sheet applying position, a small portion of the port 169 will project slightly below the lower end of the boss 126 as shown in Fig. 7, thus opening the bore in said plunger to atmosphere, whereupon the applied sheet 17 is effectively and rapidly released by the knife 118.

In accordance with another aspect of the present invention, the knife 11.9 which cooperates with the movable knife 118 in severing the sheets 17 from the tape 31 is given a short forward movement relative to the overlying tape following each sheet severing operation for the purpose of freeing the tape therefrom. In this manner buckling and jamming of the tape 31 through sticking thereof to the knife 119 is completely eliminated, and free forward movement of said tape beyond said knife in the next cycle of operation of the apparatus is positively assured. As shown, particularly in Figs. 4, 5, 7 and 8, the knife 119 is adjustably mounted on a knife-bar 17 3 by suitable means, such as bolts 171 and nuts 172. The bolts 17 pass through suitable circular openings in the bar 17 7 and through suitable slotted openings in the knife 119, and the nuts 172 are embedded in the upper surface of said knife so as to present no interference to the forward movement of the tape 31. The bar 171) is bolted or otherwise suitably secured at opposite ends thereof to and adjacent the lower ends of two vertically extending hanger-plates 173, 173 in a manner such that the knife 11) is slightly inclined lengthwise, as viewed in front elevation, Fig. 5, whereby the sheet 17 is cleanly cut from the tape 31 by a shearing action, and is slightly inclined upwardly and rearwardly, as viewed in end elevation, Fig. 4, so that when the sheet 17 is cut from the tape 31, the surface contact of said tape with the knife 119 is reduced to an absolute minimum.

The hanger-plates 173, 173 are pivotally mounted adjacent the upper ends thereof on a hinge-pin 174 which is also journalled in suitable bearings in the bracket '9'! to provide for free pivotal movement of said plates, the knife bar 179), and knife 119 as a unit. Axial displacement of the pin 174' in opposite directions is prevented by guide plates 175, 175 which are bolted or otherwise suitably secured to the bracket 97 and overlap the ends of said pin.

The front faces of the hanger-plates 173, 173 are straight for a major portion of the length thereof and terminate at their lower ends in tapered cam surfaces 176, 176. The knife 119 and plates 173, 173 are so arranged that the front or cutting edge of said knife and the front faces of said plates are in exact transverse alignment with each other, and are in exact vertical alignment with the rear or cutting edge of the movable knife 118 when the latter is in its normal raised position, as shown in Fig. 4. Resilient means, such as two small compression coil springs 177, are provided for urging the plates 173, 173 and knife 119 toward the movable knife 118 and for yieldingly holding said plates in engagement with said movable knife. The springs 177 are disposed in suitable sockets formed in the knife-bar 170 and engage against a backing-plate 178 which is bolted or otherwise suitably secured to the underside of the bracket 97. The fixed guide plates 175, 175 are so arranged that the front faces thereof are engaged by the rear or cutting edge of the movable knife 118 to guide said knife for straight-line vertical reciprocation. The rear or cutting edge of knife 118 is preferably rounded at the points of contact with the hanger-plates 173, 173 and guide plates175, 175.

It will thus appear, that when the knife 118 is moved downwardly past the knife 119 by the plunger 123, the tape 31 is moved into contact with the knife 119 and a sheet 17 is sheared from said tape. As the knife 118 continues to move downwardly with the severed sheet 17 adhering thereto, the hanger plates 173, 173, through engagement of the cam surfaces 176, 176 with said knife, are swung about the pivot 174 by the expanding action of the springs 177 to the position shown in Fig. 7, thus resulting in forward movement of the knife 119 relative to the overlying tape 31 and stripping of said tape therefrom. The tape 31 is then raised by the air jets issuing from the blow pipe 103.clear of the knife 119 for further forward movement in the next cycle of operation of the apparatus. When the knife 118 is raised and returned to its original position after the sheet 17 is applied thereby to a card 15, the knife 119 is also returned to its original sheet cutting position throughout engagement of the knife 118 with the straight front faces of the plates 173, 173 and resulting. rearward pivotal movement of said plates.

In order to insure non-contact of the adhesive coated sheets with the anvil-block 156 when applied to the cards 15, and to prevent the cards 15 from adhering to the anvil-block by vacuum created when the sheets 17 are applied and firmly pressed against said cards, a central portion of the upper surface of said block is undercut which provides a concave shallow chamber 179 (Fig. 4) which is connected with the atmosphere by two angularly related interconnected venting passages 180 and 181 also formed in said block.

The cards 15 are preferably, but not necessarily, fed automatically one after another in timed relation over the anvil-block 156 and between two grooved registering bars 182, 182 by suitable conveyor means, and stopped for a predetermined interval by suitable stop means in proper position for application of the sheets 17 to said cards and over the apertures 16 therein. Since the card conveying and stopping means form no part of the present invention, it is believed to be unnecessary to illustrate and describe the same in detail.

The operation of the apparatus constructed in accordance with the present invention will be clearly understood from the foregoing description. Although only one embodiment of the present invention has been illustrated in the accompanying drawings and described in the foregoing specification, it is to be especially understood that said invention is not limited to said embodiment or to the particular type of tape employed and article acted upon. Various modifications may be made in the structure, as well as changes in the mode of operation, assembly and manner of use, some of which have been mentioned in the foregoing specification, without departing from the spirit and scope of the invention, as will now be clear to those skilled in the art.

What is claimed is:

1. In apparatus for cutting sheets from a supply strip coated on one side thereof with pressure sensitive adhesive and applying said sheets to articles, an article support, strip severing means including a knife movable toward said support and into engagement with an article thereon, feeding means engaging only the non-adhesive side of said strip for advancing a sheet-length of said strip into operative relation with said knife, means disposed between said severing means and said feeding means for transversely bowing the advancing strip to longitudinally stiffen the same, means for actuating said knife to sever a sheet from said strip and apply said sheet to an article on said support, and gripping means associated with said knife and engaging only the non-adhesive side of said severed sheet for holding the severedsheet flatwise during transfer thereof to the article, said strip bowing means comprising fluid means acting on the adhesive side of said strip and cooperating longitudinally extending guide means engaging the non-adhesive side of said strip for forming the latter into transverse arcuate shape. under the influence of said fluid means.

2. Apparatus as defined in claim 1, wherein said knife is in the form of a horizontal plate, and said gripping means comprise a series of suction openings in and passing through the upper and lower surfaces of said plate, means for producing vacuum in said openings, and valve means for controlling the makingand breaking of vacuum in said openings at proper intervals.

3. Apparatus as defined in claim 2, comprising a reciprocal hollow plunger supporting said knife-plate and communicating with said suction openings, guide means for said plunger, said plunger being connected with said valve means and having a relief port therein normally closed by said guide means and adapted to connectwith the atmosphere when the severed sheet is moved into contact with and is applied to the article.

4. In apparatus for cutting sheets from a supply strip coated on one side thereof with a tacky adhesive and applying said sheets to articles, an article support, strip severing means including a knife movable toward said support and into engagement with an article thereon, feeding means engaging only the non-adhesive side of said strip for advancing a sheet-length of said strip beyond the cutting edge of said knife, means disposed between said severing means and said feeding means for transversely bowing the advancing strip to longitudinally stiffen the same, means for intermittently operating said feeding means, means operable during the intermittent non-feeding periods of said strip for actuating said knife to sever a sheet from said strip and apply said sheet to an article on said support, and gripping means associated With said knife and engaging only the non-adhesive side of said severed sheet for holding the severed sheet fiatwise during transfer thereof to the article, said strip bowing means comprising air blast means acting on the adhesive side of said strip and cooperating longitudinally extending guide means engaging the non-adhesive side of said strip for forming the latter into arcuate shape in transverse section under the influence of said air blast means.

5. In apparatus for cutting sheets from a supply strip thereof and applying said sheets to articles, an article support, a member mounted for sliding movement toward and away from said support, a pair of spaced driving arms mounted for pivotal movement about a common axis, means including links for pivotally connecting said arms with said member, severing means including a knife secured to said member for movement therewith, means for supplying said strip to said severing means and for feeding a sheet-length thereof beyond the cutting edgeof said knife, a bell-crank mounted for pivotal movement about said axis and disposed between said driving arms, means operatively connected with one arm of said bellcrank for imparting positive pivotal movement to the latter in opposite directions, abutment means adjustably carried by the other arm of said bell-crank and engageable with one of said driving arms for moving said member toward the support to cause said knife to sever a sheet from said strip and apply it to an article on said support, and resilient means yieldingly connecting the said other bell-crank arm with the other of said driving arms for moving said member away from said support and returning said knife to its original position.

6. Apparatus as defined in claim 5, comprising stop means for limiting the extent of movement of said member and knife away from said support by said bell-crank.

7. Apparatus as defined in claim 6, wherein said stop means comprises an abutment member adjustably carried by one of the driving arms.

8. In apparatus of the character described, feeding means for feeding a strip of thin pliable material, severing means disposed beyond said feeding means for cutting said strip into sheets of predetermined length, and means disposed between said feeding means and said severing means and including fiuid means acting on one side of the strip for transversely bowing and thereby longitudinally stiffening said strip during feeding movement thereof toward said severing means.

9. Apparatus as defined in claim 8, wherein said means for longitudinally stiffening the strip comprise means arranged at one side of the path of movement of said strip and providing a plurality of jets of air extending lengthwise of said strip and directed toward said strip, and a member arranged at the opposite side of said path and shaped to cause a transverse bowing of said strip as the latter is pressed into intimate contact with said member by said air jets.

10. Apparatus as defined in claim 9, wherein said member is V-shaped in transverse cross-section.

11. Apparatus as defined in claim 9, wherein said jets of air strike the strip with gradually diminishing intensity in the direction of feed of said strip.

12. Apparatus as defined in claim 9, wherein said air jet means comprise a blast tube angularly disposed with respect to the path of feeding movement of the strip and having therein at least one set of twin air jet openings spaced inwardly from the end thereof followed by a plurality of axially spaced single air jet openings, and comprising means for continuously supplying air under pressure to said tube.

13. In apparatus of the character described, rotary means for feeding in a horizontal plane a strip of thin pliable material having a coating of adhesive material on the underside thereof, severing means disposed beyond said rotary means for cutting said strip into sheets of predetermined length, and fluid means arranged beneath the path of movement of said strip and acting on the adhesive side of the strip for supporting and holding said strip against sagging during movement thereof toward said severing means.

14. In apparatus of the character described, rotary means for feeding a strip of thin pliable material beyond the same to a predetermined point for further action thereon, and means for longitudinally stiffening said strip as the same is fed by said rotary means, said strip stiffening means comprising a member arranged at one side of the path of movement of said strip and shaped to cause a transverse bowing of said strip, and air blast means arranged at the opposite side of said path and directed toward said strip for pressing the latter into intimate contact with said member.

15. In apparatus of the character described, severing means comprising a normally stationary knife and a cooperating movable knife for cutting individual sheets of predetermined length from a strip having a coating of adhesive material on one side thereof, rotary means for feeding said strip between said knives and with the adhesive coated side thereof facing said stationary knife, means for actuating said movable knife to sever a sheet from said strip, and means for moving said stationary knife relative to said strip and in the direction of feeding movement thereof after severance of a sheet therefrom for freeing said strip from said knife.

16. Apparatus as defined in claim 15, comprising means engaged by said movable knife and controlling the movement of said stationary knife relative to the strip.

17. In apparatus for cutting individual sheets of predetermined length from a strip having a coating of adhe sive material on one side thereof, a first knife, rotary means for feeding said strip over said knife and beyond the cutting edge thereof and with the adhesive side of said strip facing said knife, means comprising a pair of spaced plate-like members for mounting said knife for bodily pivotal movement relative to said strip, a second knife normally separated from said first knife, means for mounting said second knife for straight-line movement past said first knife, resilient means for yieldingly engaging said members with said second knife, at least one of said members extending beyond said first knife and having a cam surface thereon engageable with said second knife, and means for moving said second knife past said first knife to sever a sheet from said strip and to permit movement of said first knife by said resilient means relative to said strip through engagement of said cam surface with said second knife.

18. The method of longitudinally stiffening a strip of thin pliable material which comprises flowing against one surface of the strip and holding the strip at the opposite surface thereof so as to cause it to assume an arcuate shape in transverse section.

References Cited in the file of this patent UNITED STATES PATENTS 676,244 Sherman June 11, 1901 1,161,346 Schmidt Nov. 23, 1915 1,282,314 Swift Oct. 22, 1918 1,968,881 Edwards Aug. 7, 1934 2,033,849 Mudd Mar. 10, 1936 2,061,524 Storck Nov. 17, 1936 2,061,968 Kath Nov. 24, 1936 2,072,875 Gray Mar. 9, 1937 2,158,790 Arthur May 16, 1939 2,234,017 Bauer Mar. 4, 1941 2,266,362 Forster Dec. 16, 1941 2,275,409 Anderson Mar. 10, 1942 2,285,507 Gilliam June 9, 1942 2,289,336 Bamford July 14, 1942 2,334,224 Socke Nov. 16, 1943 2,382,406 Engberg Aug. 14, 1945 2,493,159 Morrison Ian. 3, 1950 2,555,218 Bailey May 29, 1951 FOREIGN PATENTS 436,743 Germany Nov. 6, 1926 

